[[Image:EDTA with ligand.png|right|thumb|200px|'''EDTA''' (black) with coordinate bonds to a metal ion (red)]]

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'''EDTA''' stands for '''ethylene-diamine-tetraacetic acid'''. It chelates divalent cations and is therefore used in many buffers. Its relative [[EGTA]] has a higher affinity for calcium than EDTA.

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'''EDTA''' stands for '''ethylene-diamine-tetraacetic acid'''. It chelates divalent cations and is therefore used in many buffers. Its relative [[EGTA]] has a higher affinity for calcium than for magnesium ions.

==Purpose==

==Purpose==

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=== 0.5 M EDTA stock ===

=== 0.5 M EDTA stock ===

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* 16.81 g EDTA (Sodium Salt)

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* 18.61 g EDTA (Sodium Salt)

* dH2O to 90 ml

* dH2O to 90 ml

* adjust pH to 7.0

* adjust pH to 7.0

Revision as of 18:48, 9 February 2011

chemical structure of EDTA - ethylene-diamine-tetraacetic acid

EDTA (black) with coordinate bonds to a metal ion (red)

EDTA stands for ethylene-diamine-tetraacetic acid. It chelates divalent cations and is therefore used in many buffers. Its relative EGTA has a higher affinity for calcium than for magnesium ions.

0.5 M EDTA stock

0.5M 500ml pH 8.0 with NaOH pre-calculated

Storage and stability

store at room temperature

stable for years

Interesting facts

Here's an article that speaks of the wonders of EDTA and how it can help treat Aunt Edna's cardiovascular disease, enhance your enjoyment of the Friday night happy hour, and act as a "get out of jail free" card.

Safety

?

References

Here's a great page about EDTA, including formation constant (Kf) values for metal-EDTA complexes. Note that many heavy metal ions (like Fe3+, Co2+, and Zn2+) are chelated much more strongly than Mg2+. A little bit of EDTA in your reaction will go a long way to keep these evildoers out of trouble and away from your precious biomolecules without interfering with your Mg2+-dependent reactions.